Prospecting for Oil or Gold? Check the Time: Advances in atomic clocks allow detailed relativistic measurements

Prospecting for Oil or Gold? Check the Time

Prospecting for Oil or Gold? Check the Time: Advances in atomic clocks allow detailed relativistic measurements

Clocks low in the gravity well run slower than those higher up. That’s just a relativistic fact of life—one that we take advantage of every time we use the Global Positioning System. (I remember how cool I thought it was when I first learned that clocks in orbiting GPS satellites have to be programmed to correct for relativistic time dilation.) Within the past year, experimentalists comparing t he speeds of widely separated atomic clocks (connected via fiber optic cable) have shown that current chronometers, with uncertainties around 10-16 , are sensitive enough to detect the change in time’s flow that accompanies a shift of a meter or less in relative elevation. The geoid is the Earth-swaddling surface of equal gravitational potential that more or less coincides with global mean sea level. Or, from the chronometric viewpoint, the surface on which all clocks tick at the sa...

Full article: http://spectrum.ieee.org/tech-talk/at-work/test-and-measu...

Tweets

@MarianneGie » 13 Dec '12, 12am
Next gen. atomic clocks will help us map the earth's interior: [link]
@OBASHI_Chief » 15 Nov '12, 2pm
Prospecting for Oil or Gold? Check the Time [link] | #gps #data #science
@GetGlobalEdge » 15 Nov '12, 10am
Aerospace _/~ Prospecting for Oil or Gold? Check the Time: Advances in atomic clocks allow de... [link] #aero #space #tech
@IEEE_TA » 15 Nov '12, 12am
#IEEE #Aerospace Prospecting for Oil or Gold? Check the Time [link]
@FrankAldorf » 14 Nov '12, 7pm
Prospecting for Oil or Gold? Check the Time: Advances in atomic clocks allow detailed relativistic measure... [link] #work
@xvdr » 14 Nov '12, 6pm
Prospecting for Oil or Gold? Check the Time [link] #tech #science
@IEEEGreen » 14 Nov '12, 6pm
Prospecting for Oil or Gold? Check the Time [link] #IEEE #IEEEGreen
@IEEESpectrum » 14 Nov '12, 6pm
Prospecting for Oil or Gold? Check the Time: Advances in atomic clocks allow detailed relativistic measurements ... [link]
@juank_astu » 14 Nov '12, 6pm
Prospecting for Oil or Gold? Check the Time: Advances in atomic clocks allow detailed relativistic measurements ... [link]
@HowonKim2 » 14 Nov '12, 6pm
Prospecting for Oil or Gold? Check the Time: Advances in atomic clocks allow detailed relativistic measurements ... [link]
@nsisongeffiong » 14 Nov '12, 6pm
Prospecting for Oil or Gold? Check the Time [link]
@electrosoftinc » 14 Nov '12, 6pm
Prospecting for Oil or Gold? Check the Time [link]
@wkenneth » 14 Nov '12, 6pm
Prospecting for Oil or Gold? Check the Time: Advances in atomic clocks allow detailed relativistic measurements ... [link]